Apparatus for performing an electrosurgical procedure

ABSTRACT

An endoscopic forceps is provided and includes a housing having a shaft. An end effector assembly operatively connects to a distal end of the shaft and has a pair of first and second jaw members. One of the first and second jaw members is movable relative to the other jaw member from an open position, to a clamping position. One of the first and second jaw members includes one or more cam slots defined therein and configured to receive a cam member that upon movement thereof rotates the movable jaw member from the open position to the clamping position. A resilient member is operably coupled to the jaw member that includes the one or more cam slots. The resilient member is configured to provide a camming force to the cam slot and to bias the first and second jaw members in the clamping position.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of and claims thebenefit of and priority to U.S. patent application Ser. No. 12/792,019filed on Jun. 2, 2010 by Kerr et al., now U.S. Pat. No. 8,409,246, theentire contents of which is hereby incorporated by reference.

BACKGROUND

Technical Field

The present disclosure relates to an apparatus for performing anelectrosurgical procedure. More particularly, the present disclosurerelates to an electrosurgical apparatus including an end effectorassembly having a pair of jaw members providing a mechanical advantageat the end effector.

Description of Related Art

Electrosurgical instruments, e.g., electrosurgical forceps (open orclosed type), are well known in the medical arts and typically include ahousing, a handle assembly, a shaft and an end effector assemblyattached to a distal end of the shaft. The end effector includes jawmembers configured to manipulate tissue (e.g., grasp and seal tissue).Typically, the electrosurgical forceps utilizes both mechanical clampingaction and electrical energy to effect hemostasis by heating the tissueand blood vessels to coagulate, cauterize, seal, cut, desiccate, and/orfulgurate tissue. Typically, one or more driving mechanisms, e.g., adrive assembly including a drive rod, is utilized to cooperate with oneor more components operatively associated with the end effector toimpart movement to one or both of the jaw members.

In certain instances, to facilitate moving the jaw members from an openposition for grasping tissue to a closed position for clamping tissue(or vice versa) such that a consistent, uniform tissue effect (e.g.,tissue seal) is achieved, one or more types of suitable devices may beoperably associated with the electrosurgical forceps. For example, insome instances, one or more types of springs, e.g., a compressionspring, may operably couple to the handle assembly associated with theelectrosurgical forceps. In this instance, the spring is typicallyoperatively associated with the drive assembly to facilitate actuationof a movable handle associated with the handle assembly to ensure that aspecific closure force between the jaw members is maintained within oneor more suitable working ranges.

In certain instances, the shaft may bend or deform during the course ofan electrosurgical procedure. For example, under certain circumstances,a clinician may intentionally bend or articulate the shaft to gaindesired mechanical advantage at the surgical site. Or, under certaincircumstances, the surgical environment may cause unintentional orunwanted bending or flexing of the shaft, such as, for example, in theinstance where the shaft is a component of a catheter basedelectrosurgical forceps. More particularly, shafts associated withcatheter-based electrosurgical forceps are typically designed tofunction with relatively small jaw members, e.g., jaw members that areconfigured to pass through openings that are 3 mm or less in diameter.Accordingly, the shaft and operative components associated therewith,e.g., a drive rod, are proportioned appropriately. That is, the shaftand drive rod are relatively small.

As can be appreciated, when the shaft is bent or deformed (eitherintentionally or unintentionally) the frictional losses associated withdrive rod translating through the shaft are transferred to the spring inthe housing, which, in turn, may diminish, impede and/or preventeffective transfer of the desired closure force that is needed at thejaw members. Moreover, the frictional losses may also lessen theoperative life of the spring, which, in turn, ultimately lessens theoperative life of the electrosurgical instrument.

SUMMARY

The present disclosure provides an endoscopic forceps. The endoscopicforceps includes a housing having a shaft. An end effector assemblyoperatively connects to a distal end of the shaft and has a pair offirst and second jaw members. One of the first and second jaw members ismovable relative to the other jaw member from an open position, to aclamping position. One of the first and second jaw members includes oneor more cam slots defined therein and configured to receive a cam memberthat upon movement thereof rotates the movable jaw member from the openposition to the clamping position. A resilient member is operablycoupled to the jaw member that includes the one or more cam slots. Theresilient member is configured to provide a camming force to the camslot and to bias the first and second jaw members in the clampingposition.

The present disclosure provides an end effector adapted for use with aforceps including at least one shaft. The first and second jaw membersoperably couples to a distal end of the shaft. One or both of the firstand second jaw members is movable relative to the other from an openposition, to a clamping position. One of the first and second jawmembers includes one or more cam slots defined therein and configured toreceive a cam member that upon movement thereof rotates the jaw membersfrom the open position to the clamping position. A resilient member isoperably coupled to the jaw member that includes the at least one camslot. The resilient member is configured to provide a camming force tothe cam slot and to bias the first and second jaw members in theclamping position.

BRIEF DESCRIPTION OF THE DRAWING

Various embodiments of the present disclosure are described hereinbelowwith references to the drawings, wherein:

FIG. 1A is a side, perspective view of an endoscopic bipolar forcepsshowing an end effector assembly including jaw members according to anembodiment of the present disclosure;

FIG. 1B is a side, perspective view of the endoscopic bipolar forcepsdepicted in FIG. 1A illustrating internal components associated with ahandle assembly associated with the endoscopic bipolar forceps;

FIG. 2 is a schematic view of a jaw member including a jaw housingdepicted in FIGS. 1A and 1B;

FIG. 3 is a schematic view of a jaw member including a jaw housingaccording to another embodiment of the present disclosure;

FIG. 4 is a schematic view of a jaw member including jaw housingaccording to yet another embodiment of the present disclosure;

FIG. 5 is a schematic view of a jaw member including jaw housingaccording to still another embodiment of the present disclosure;

FIG. 6 is a schematic view of a jaw member including jaw housingaccording to still yet another embodiment of the present disclosure;

FIG. 7 is a schematic view of a jaw member including jaw housingaccording to still yet another embodiment of the present disclosure;

FIG. 8 is a schematic view of a jaw member including jaw housingaccording to still yet another embodiment of the present disclosure;

FIG. 9 is a schematic view of a jaw member including jaw housingaccording to still yet another embodiment of the present disclosure;

FIG. 10 is a schematic view of jaw members including respective jawhousings according to still yet another embodiment of the presentdisclosure; and

FIG. 11 is a schematic view of jaw members including respective jawhousings according to still yet another embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Detailed embodiments of the present disclosure are disclosed herein;however, the disclosed embodiments are merely examples of thedisclosure, which may be embodied in various forms. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one skilled in the art to variouslyemploy the present disclosure in virtually any appropriately detailedstructure.

With reference to FIGS. 1A and 1B, an illustrative embodiment of anelectrosurgical apparatus, e.g., a bipolar forceps 10 is shown. Bipolarforceps 10 is operatively and selectively coupled to a suitable energysource, such as, for example, an electrosurgical generator (not shown),for performing an electrosurgical procedure. As noted above, anelectrosurgical procedure may include sealing, cutting, cauterizing,coagulating, desiccating, and fulgurating tissue all of which may employRF energy. The generator may be configured for monopolar and/or bipolarmodes of operation. The generator may include or is in operativecommunication with a system (not shown) that may include one or moreprocessors in operative communication with one or more control modulesthat are executable on the processor. The control module (not explicitlyshown) may be configured to instruct one or more modules to transmitelectrosurgical energy, which may be in the form of a wave orsignal/pulse, via one or more cables (e.g., a cable 310) to one or bothseal plates 118, 128.

Bipolar forceps 10 is shown configured for use with variouselectrosurgical procedures and generally includes a housing 20, anelectrosurgical cable 310 that connects the forceps 10 to a source ofelectrosurgical energy (e.g., electrosurgical generator not shown), ahandle assembly 30, a rotating assembly 80, a trigger assembly 70, adrive assembly 130 (see FIG. 1B), and an end effector assembly 100 thatoperatively connects to the drive assembly 130 and includes a driveelement 150. The drive assembly 130 may be in operative communicationwith handle assembly 30 for imparting movement of one or both of a pairof jaw members 110, 120 of end effector assembly 100. Conventional driveassemblies typically utilize one or more types of springs, e.g., acompression spring, to facilitate closing the jaw members 110 and 120.For illustrative purposes, a compression spring 131 (see FIG. 1B) isshown separated from the housing 20. End effector assembly 100 includesopposing jaw members 110 and 120 (FIGS. 1A and 1B) that mutuallycooperate to grasp, seal and, in some cases, divide large tubularvessels and large vascular tissues.

With continued reference to FIGS. 1A and 1B, forceps 10 includes a shaft12 that has a distal end 14 configured to mechanically engage the endeffector assembly 100 and a proximal end 16 that mechanically engagesthe housing 20. In the drawings and in the descriptions that follow, theterm “proximal,” as is traditional, will refer to the end of the forceps10 that is closer to the user, while the term “distal” will refer to theend that is farther from the user.

Handle assembly 30 includes a fixed handle 50 and a movable handle 40.Fixed handle 50 is integrally associated with housing 20 and handle 40is movable relative to fixed handle 50. Movable handle 40 of handleassembly 30 is ultimately connected to the drive assembly 130, whichtogether mechanically cooperate to impart movement of one or both of thejaw members 110 and 120 to move from an open position, wherein the jawmembers 110 and 120 are disposed in spaced relation relative to oneanother, to a clamping or closed position, wherein the jaw members 110and 120 cooperate to grasp tissue therebetween.

Jaw members 110, 120 are operatively and pivotably coupled to each otherand located adjacent the distal end 14 of shaft 12. For illustrativepurposes, the end effector 100 is shown including a unilateral jawconfiguration, i.e., jaw member 110 is movable with respect to jawmember 120 that is non-movable or stationary with respect to jaw member110. In the illustrated embodiment, the jaw member 110 is movable from anormally open configuration to the clamping configuration when themovable handle is moved proximally, see FIGS. 1A and 1B, respectively.Respective electrically conductive seal plates 118 and 128 are operablysupported on and secured to jaw housings 117 and 127 of respective thejaw members 110 and 120, described in greater detail below. For thepurposes herein, jaw members 110 and 120 include jaw housings 117 and127 and sealing plates 118 and 128, respectively. Jaw housings 117 and128 are configured to support the seal plates 118 and 128, respectively.

For a more detailed description of the bipolar forceps 10 includinghandle assembly 30 including movable handle 40, rotating assembly 80,trigger assembly 70, drive assembly 130, jaw members 110 and 120(including coupling methods utilized to pivotably couple the jaw members110 and 120 to each other) and electrosurgical cable 310 (includingline-feed configurations and/or connections), reference is made tocommonly owned U.S. Pat. Publication No. 2007/0173814 filed on Nov. 9,2006.

Turning now to FIG. 2, one embodiment of jaw housing 117 is shown. Itshould be noted that, in one embodiment, jaw housings 117 and 127 aresubstantially identical to each other, and, in view thereof, and so asnot to obscure the present disclosure with redundant information, theoperative components associated with the jaw housing 117 are describedin further detail with respect to jaw member 110, and only thosefeatures distinct to housing 127 will be described hereinafter.

With continued reference to FIG. 2, jaw member 110, jaw housing 117, andoperative components associated therewith may be formed from anysuitable material, including but not limited to metal, metal alloys,plastic, plastic composites, etc. In the embodiment illustrated in FIG.2, jaw member 110 is formed from metal.

A distal end 117 a of the jaw member 110 may be configured to securelyengage the electrically conductive seal plate 118 or, with respect to amonolithic jaw member, form the seal plate 118.

A portion of a proximal end 117 b of the jaw member 110 is operablysecured to the distal end 14 of the shaft 12. More particularly, aportion of proximal end 117 b operably couples to the distal end 14 andis in operative communication with a cam member 205 that is operablycoupled (via one or more suitable coupling methods, e.g., brazing) tothe drive element 150 of the drive assembly 130 such that movement ofthe drive element 150 causes one or, in some instances, both of the jawmembers 110 and 120 to move from the opened position to the closed orclamping position. For example, in one particular embodiment, when thedrive element 150 is “pulled,” i.e., moved or translated proximally, oneor both of the jaw members 110 and 120 is/are caused to move toward theother. Alternatively, and if desired, the drive assembly 130 includingthe drive element 150 may be configured such that when the drive element150 is “pushed,” i.e., moved or translated distally, one or both of thejaw members 110 and 120 are caused to move toward each other. In certaininstances, it may prove useful to have a drive element 150 that isflexible. More particularly, in the illustrated embodiments, where thedrive element 150 is operatively associated with an endoscopicinstrument (e.g., a bipolar forceps 10 that has a flexible shaft and isconfigured with jaws associated therewith that are typically quitesmall, i.e., 3 mm-5 mm), the drive element 150 may be substantiallyflexible to accommodate bends typically associated with shaft 12 whenthe bipolar forceps 10 is remotely actuatable relative to the patient.

Proximal end 117 b of the jaw member 110 is configured to support one ormore resilient members 204. To this end, proximal end 117 b of the jawhousing 117 includes a notched area or channel 206 defined by two raisedportions 208 and 210. The notched area 206 is configured to securelyhouse a portion of the resilient member 204, described in greater detailbelow. A raised protrusion or pin 212 of suitable proportion isconfigured to securely engage the resilient member 204.

Resilient member 204 is operably associated with the housing 117. Moreparticularly, one or more types of resilient members e.g., a resilientmember 204, may be utilized to generate a closure force at the jawmembers 110 and 120 of the end effector 100 when the jaw members 110 and120 are in a closed or clamped position. In one embodiment, theresilient member 204 cooperates with the drive assembly 130 to provide aclosure force on the jaw members 110 and 120 for sealing tissue, e.g.,in the range of about 3 kg/cm² to about 16 kg/cm². Resilient member 204includes an opening 214 (shown engaged with protrusion 212 and as suchnot explicitly visible) that is defined at a proximal end of theresilient member 204 that securely engages protrusion 212. An elongatedportion 216 defining a cam slot 218 extends from the proximal end of theresilient member 204 adjacent the opening 214 and engages cam member 205that is operably associated with the drive member 150. Specifically, camslot 218 is configured to receive cam member 205 (see FIG. 2) and isoperably formed and/or positioned at the proximal end 117 b of the jawhousing 117. More specifically, cam slot 218 includes a generallyoblique configuration with respect to a longitudinal axis “B-B” that isparallel to a longitudinal axis “A-A” defined through the shaft 12, seeFIGS. 1A and 1B in combination with FIG. 2. Cam slot 218 may extend atan angle that ranges from about 5° to about 30° with respect to thelongitudinal axis “B-B.” In the embodiment illustrated FIG. 2, cam slot218 extends at angle that is approximately equal to 45° with respect tothe longitudinal axis “B-B.” The angle of the cam slot 218 may beselectively varied depending upon a particular instrument, use ormanufacturing preference. A proximal end 207 of the cam slot 218 isconfigured to contact a stop 209 that is operably associated with theshaft 12 and/or end effector 100 such that the jaw member 110 isprevented from rotating past a predetermined point, described in moredetail below. A portion of the proximal end of the resilient member 204is securely housed within the notched area 206 of the jaw housing 117.More particularly, a finger 220 of suitable proportion extends from theproximal end of the resilient member 204 and is securely housed withinthe notched area 206. The finger 204 is configured to contact one orboth of the raised portions 208 and 210 when the jaw member 110 is movedfrom the open position to the clamping position.

One or more suitable pivot mechanisms may be operably associated withthe jaw housing 117 to provide a point of pivot for one or both of thejaw members 110 and 120. For example, a pivot pin 222 may be operablydisposed on jaw housing 117 and operably couples to an aperture oropening (not explicitly shown) disposed on the jaw housing 117 (FIG. 2)adjacent the distal end 117 a of the jaw housing 117.

One or more type of lubricious materials (not shown), e.g., PTFE, maycoat cam slot 218 and/or an internal portion of the elongated portion216. Coating the cam slot 218 with the lubricious material facilitatesmovement of the cam member 205 within the cam slot 218 when the driveelement is translated proximally (or distally).

Stop 209 is operably disposed adjacent the resilient member 204. Stop209 functions to provide the proper amount of deflection for theresilient member 204 such that a closure force in the range of about 3kg/cm² to about 16 kg/cm² is present between the jaw members 110 and 120when the jaw members 110 and 120 are in the clamping position. To thisend, stop 209 includes a generally triangular configuration having asloped or angled distal leading end 213 that is substantially parallelto the elongated portion 216 and cam slot 218 when cam member 205 ispositioned at a distal end of the cam slot 218. Stop 209 may be madefrom any suitable material including but not limited to metal, plastic,etc. In the illustrated embodiment, stop 209 is monolithically formedwith the end effector 100 and includes a substantially rigidconfiguration. In certain embodiments, it may prove useful to make stop209 relatively resilient. Stop 209 is configured to contact a portion,e.g., proximal end 207 of elongated portion 216, of the resilient member204 when the cam member 205 is translated a predetermined distanceproximally within the cam slot 218. More particularly, when the movablehandle 40 moves proximally, the drive element 150 moves proximally,which, in turn, causes the cam member 205 to move proximally from aninitial position (shown in phantom in FIG. 2) that corresponds to thejaw member 110 being in the open position, to a subsequent, or final,position that corresponds to the jaw member 110 being in the clampingposition (FIG. 2). As the cam member 205 moves from the initial positiontowards the final position, the elongated portion 216 including the camslot 218 of the resilient member 204 moves proximally towards the stop209, which, in turn, causes the resilient member 204 to deflect.Deflection of the resilient member 204 causes the jaw member 110 to movefrom the open position towards the clamping position. When the elongatedportion 216 including the cam slot 218 moves a predetermined distance,the stop 209 and proximal end 207 of the elongated portion 216 areconfigured to contact each other (FIG. 2). Contact between the stop 209and proximal end 207 results in the proper amount of deflection for theresilient member 204 and, thus, the necessary closure force neededbetween the jaw members 110 and 120.

In an assembled configuration each of the jaw members 110 and 120 arepositioned in side-by-side relation. As noted above, the cam member 205is operably coupled to the drive element 150 (or other suitable drivingdevice) and is positioned within the cam slot 218 operably associatedwith the jaw member 110. Pivot pin 222 is positioned within the openingassociated with jaw member 110. As noted above, the pivot pin 222provides a point of pivot for the jaw member 110. Once assembled, thejaw member 110 and/or jaw member 120 may be pivotably supported at thedistal end 14 of the shaft 12 by known methods, such as, for example, bythe method described in commonly-owned U.S. Pat. No. 7,597,693 toGarrison filed on Jun. 13, 2003.

In the instance where the end effector 100 includes a bilateral jawconfiguration, each of jaw members 110 and 120 includes a respectiveresilient member 204 with an elongated portion 216 including a cam slot218. In this instance, the drive element 150 may be configured toaccommodate movement of both of the jaw members 110 and 120. Forexample, the drive element 150 may include a bifurcated distal end thatis configured to operably couple to a respective cam slot 218. In thisinstance, each of the bifurcated ends may include a respective cammember 205 that operably couples to a respective cam slot 218. It willbe appreciated that other configurations of the drive element 150 may beutilized to effect movement of the jaw members 110 and 120 when the jawmembers 110 and 120 employed in the bilateral configuration.

Operation of the forceps 10 is now described in terms of use with theend effector 100 illustrated in FIGS. 1A and 1B, i.e., an end effector100 that utilizes a unilateral jaw configuration.

In use, jaw member 110 is initially in an open position. Tissue ispositioned between the jaw members 110 and 120 and, subsequently,movable handle 40 is moved proximally. Proximal movement of movablehandle 40 causes the drive element 150 to move proximally. Proximalmovement of the drive element 150 causes cam member 205 positionedwithin the cam slot 218 on jaw housing 117 to move proximally againstthe bias of the resilient member 204, which, in turn, causes jaw member110 to move toward jaw member 120, such that tissue is clamped betweenthe jaw members 110 and 120. When the cam member 205 is moved, i.e.,“pulled,” to a set position, e.g., a position when the jaw members 110and 120 are in the closed or clamped position and where the proximal end207 of elongated portion 216 contacts the distal leading end 213 of thestop 209, the biased cam member 205 generates a sealing or closure forceat the jaw members 110 and 120. The combination of jaw housing 117 witha resilient member 204 provides a consistent, uniform tissue effect,e.g., tissue seal. Moreover, the combination of jaw housing 117 andresilient member 204 (or other suitable springs, e.g., leaf spring)provides an additional mechanical advantage at the jaws 110 and 120.More particularly, the frictional losses that are associated with aforceps when a drive element is translated within a shaft is offloadedand/or diminished by the resilient member 204 operably associated withthe jaw housing 117.

With reference now to FIG. 3, an alternate embodiment of a jaw housingis shown designated jaw housing 317. Jaw housing 317 is similar to jawhousings 117 and so as not to obscure the present disclosure withredundant information, only those operative features and components thatare unique to jaw housing 317 are described. For illustrative purposes,jaw housing 317 and operative components associated therewith aredescribed in terms of use with jaw member 110.

In the embodiment illustrated in FIG. 3, one or more types of resilientor spring-like structures are monolithically formed with the jaw housing317 during the manufacturing process. Monolithically forming the jawhousing 317 with a resilient member(s) decreases the amount of workingcomponents, e.g., resilient member 204, needed to provide the closure orsealing forces, e.g., in the range of about 3 kg/cm² to about 16 kg/cm²or about 120 pounds per square inch, at the jaw members 110 and 120,which, in turn, reduces the overall cost in the manufacture of the endeffector 100 and/or jaw members 110 and 120.

With continued reference to FIG. 3, a resilient member 304 of suitableproportion is operably associated with the jaw housing 317. Moreparticularly, resilient member 304 is monolithically formed, e.g.,molded, with the jaw housing 317. Alternatively, resilient member 304may be a separate component, e.g., coil spring, leaf spring, resilientmember 204, etc., that is operably coupled to the jaw housing 317 by anysuitable method(s). The amount of flexibility of the resilient member304 may be dependent on the type of material of the resilient member 304is made from, the dimensions associated with the resilient member 304,and/or one or more other variables not explicitly described herein. Inthe illustrated embodiment, resilient member 304 is made from the samematerial, e.g., metal, as the jaw member 110. Accordingly, the dimensionof the resilient member 304 is designed appropriately such that adesired amount of “flex” is obtained when a cam member 305 is translatedwithin an elongated member 316 that defines a generally elongated camslot 302. Resilient member 304 extends from a bottom wall 306 of aproximal end 317 b of the jaw housing 317. More particularly, resilientmember 304 includes a generally elongated upright portion 308 thatextends in a generally orthogonal orientation from bottom wall 306 whenthe jaw member 110 is in an open position (not explicitly shown).Upright portion 308 of resilient member 304 supports and/or couples toelongated member 316. Cam slot 302 is dimensioned to house a cam member305 and configured to move the jaw member 110. This configuration of anupright portion 308 facilitates flexing or pivoting the elongated camslot 302 when cam member 305 is moved proximally within the elongatedcam slot 302. Cam member 305 is configured and operates similar to otherpreviously described cam members, e.g., cam member 205. Moreparticularly, cam member 305 operably couples to a drive element 150 andis configured to translate within the elongated cam slot 302 when thedrive element 150 is translated proximally or, in some instances,distally.

A pivot pin 322 is operably disposed on the jaw housing 317. Pivot pin322 functions in a manner that is substantially similar to that of pivotpin 222. Accordingly, pivot pin 322 is not described in further detail.

A stop 309 is operably disposed adjacent the elongated cam slot 302 andis configured to function similarly to that of stop 209. Moreparticularly, stop 309 is configured to contact a portion, e.g., atrailing edge or proximal end 307, of elongated cam slot 302 when thecam member 305 is translated proximally within the elongated cam slot302. A distinguishing feature of the stop 309 when compared to stop 209is the general shape of the stop 309. More particularly, in theillustrated embodiment, a leading end 313 of the stop 309 is disposed ina generally orthogonal orientation with respect the elongated cam slot302 as opposed to a parallel orientation as described above with respectto leading end 213 of stop 209 and cam slot 218.

Operation of the jaw housing 317 is substantially similar to that of jawhousing 117. As a result thereof, only those operative features that areunique to jaw housing 317 are described in detail.

In use, proximal movement of the drive element 150 causes cam member 305positioned within the cam slot 302 on jaw housing 317 to move proximallyagainst the bias of the resilient member 304, which, in turn, causes oneor both of the jaw members, e.g., jaw member 110 to move toward theother jaw member, e.g., jaw member 120, such that tissue is clampedbetween the jaw members 110 and 120. When the cam member 305 is moved,i.e., “pulled,” to a set position, e.g., a position when the jaw members110 and 120 are in the closed or clamped position and when the elongatedmember 316 contacts the leading end 313 of the stop 309, the biased cammember 305 generates the appropriate closure force at the jaw members110 and 120.

With reference to FIGS. 4 and 5, alternate embodiments of amonolithically formed resilient member that may be utilized with arespective jaw housing 417 and 517 are shown. More particularly, in theembodiments illustrated in FIGS. 4 and 5 each of jaw housing 417 and 517includes a generally rectangular configuration with one or more cut-outsthat serve as a resilient member that provide the closure or sealingforces, e.g., in the range of about 3 kg/cm² to about 16 kg/cm², at thejaw members 110 and 120, which, in turn, reduces the overall cost in themanufacture of the end effector 100 and/or jaw members 110 and 120.

With reference now to FIG. 4, jaw housing 417 includes a cam slot 402that is configured to house a cam member 405. The configuration of camslot 402 and cam member 405 is similar to that of cam slot 218 and cammember 205. A distinguishing feature of the cam slot 402 when comparedthe cam slot 218 is that the cam slot 402 includes a generally elongatedextension 409 that provides a degree of compliancy to the cam slot 402.A pivot pin 422 couples to the jaw housing 417 and functions in a mannersimilar to that of the previously described pivot pins, e.g., pivot pin322.

A slit 403 is operably disposed along a length of a proximal end 417 bof the jaw housing 417. Specifically, slit 403 is operably positionedalong a length of the jaw housing 417 adjacent the cam slot 402. Morespecifically, a generally “L” shaped slit 403 is positioned proximallywith respect to cam slot 402. In the embodiment illustrated in FIG. 4,an area (indicated by phantom lines) between the slit 403 and cam slot402 serves as a resilient beam or cushion 407 that provides a degree offlexibility when the cam member 405 is translated proximally within thecam slot 402.

In use, proximal movement of the drive element 150 causes cam member 405positioned within the cam slot 402 on jaw housing 417 to move proximallyagainst the bias of the cushion 407, which, in turn, causes one or bothof the jaw members, e.g., jaw member 110 to move toward the other jawmember, e.g., jaw member 120, such that tissue is clamped between thejaw members 110 and 120. When the cam member 405 is moved, i.e.,“pulled,” to a set position, e.g., a distal most position within the camslot 402, the biased cam member 405 generates a closure force at the jawmembers 110 and 120.

With reference now to FIG. 5, jaw housing 517 includes a monolithicallyformed notched area 501 having suitable dimensions. More particularly,notched area 501 creates a cantilever beam spring configuration. Moreparticularly, the cantilever beam spring configuration is defined bynotched area 501 that includes three sidewalls 506 that collectivelydefine a generally slanted base section 508 of suitable dimensions. Apair of sidewalls 510 extends from the base section 508. The pair ofsidewalls 510 extends orthogonally from the base section 508 and isslanted with respect to the longitudinal axis “B-B.” The pair ofsidewalls 510 operably couples the base section 508 to a spring arm 501that forms one side of a cam slot 502. Cam slot 502 is dimensioned tohouse a cam member 505. In the embodiment illustrated in FIG. 5, camslot 502 is proportionally larger than the pair of sidewalls 510. Moreparticularly, the pair of sidewalls 510 defines a width (or in someinstances may be wider) that is smaller than a width of the cam slot502. The smaller width of the pair of sidewalls 510 facilitates flexingor pivoting the cam slot 502 when cam member 505 is moved proximallywithin the cam slot 502.

In use, proximal movement of the drive element 150 causes cam member 505positioned within the cam slot 502 on jaw housing 517 to move proximallyagainst the bias of the cam slot 502 that serves as a spring arm, which,in turn, causes one or both of the jaw members, e.g., jaw member 110, tomove toward the other jaw member, e.g., jaw member 120, such that tissueis clamped between the jaw members 110 and 120. When the cam member 405is moved, i.e., “pulled,” to a set position, e.g., a distal mostposition within the cam slot 502, the biased cam member 505 generates aclosure force at the jaw members 110 and 120.

With reference to FIGS. 6-8, alternate embodiments of a monolithicallyformed resilient member that may be utilized with respective jawhousings 617-817 are shown. More particularly, in the embodimentsillustrated in FIGS. 6-8 each of jaw housing 617-817 includes agenerally rectangular configuration with one or more slits or cut-outsthat serve as or house a resilient member that provides the requisiteclosure or sealing forces, e.g., in the range of about 3 kg/cm² to about16 kg/cm², at the jaw members 110 and 120.

With reference to the FIG. 6, jaw housing 617 includes one or morecompression slits or cut-outs 603. In the embodiment illustrated in FIG.6, jaw housing 617 includes a generally spiral shaped compression slit603 (slit 603) that is operably disposed along a length of a proximalend 617 b of the jaw housing 617. Specifically, slit 603 includes twonon-intersecting branches 605 and 607 that meet at a location that isadjacent to pivot 622 that pivotably couples jaw member 110 to the shaft12. More specifically, each of the branches 605 and 607 wraps around thepivot 622 and extends along a generally spiral path throughout theproximal end 617 b of the jaw housing 617. In the embodiment illustratedin FIG. 6, the slit 603 serves as a resilient member or cushion thatprovides a degree of flexibility when the drive element 150 is movedproximally. The drive element 150 operably couples to a bottom portion617 c of the proximal end 617 b of the jaw housing 617 via one or morecoupling methods, e.g., a pin or rivet 151. Pivot 622 is rigidlyattached to boss 623 which prevents pivot post 622 from rotating. Ratherjaw housing 617 with slots 605 and 607 are allowed to rotate aroundpivot post 622 while either tensioning or relaxing spring member 624.Spring member 624 may be biased to hold the jaw members 110 and 120either in the open or closed position when the device is at rest. Boss623 may be part of shaft 12 or a separate part attached to shaft 12. Inthe embodiment illustrated in FIG. 6, the slit 603 maintains the jawmember 110 in the clamping position and generates the appropriateclosure force at the jaw members 110 and 120.

In use, proximal movement of the drive element 150 causes jaw member 110to rotate and move away from the jaw member 120 such that tissue may bepositioned therebetween. Thereafter, movable handle 40 is releasedwhich, in turn, causes the drive element 150 to move distally and thejaw member 110 to move back to the clamping position such that tissue isclamped between the jaw members 110 and 120. When the jaw members 110and 120 are in the clamping position, the slit 603 is configured togenerate the appropriate closure force, e.g., in the range of about 3kg/cm² to about 16 kg/cm², between the jaw members 110 and 120.

With reference to the FIG. 7, jaw housing 717 includes a cavity 703.Cavity 703 is configured to house one or more types of resilient members704. In the embodiment illustrated in FIG. 7, the resilient member 704is a monolithically formed resilient member in the form of a compressionspring 704. The compression spring 704 is configured to expand andcontract within the confines of the cavity 703. The compression spring704 is disposed below a pivot pin 722 to facilitate rotating the jawmember 110. The drive element 150 operably couples to a proximal end 704b of compression spring 704 by one or more suitable coupling methods,e.g., a rivet or pin 151. In the embodiment illustrated in FIG. 7, thecompression spring 704 does not bias the jaw member 110 in either theopen position or closed position. Rather, compression spring 704 servesto regulate the clamping force of jaw member 110 when drive member 150is moved distally or proximally.

In the embodiment illustrated in FIG. 7, the drive member 150 biases thejaw member 110 closed when moved distally and open when movedproximally. The at rest gap “g” may be adjusted to achieve a desiredopening and closing force regulation.

Optionally, compression spring 704 may be formed from the base jawmaterial of jaw member 110 as shown, or it may be inserted as a separatepart made from other suitable material. As such, a separate compressionspring 704 may be longer than cavity 703 in its free state and it couldbe compressed upon assembly into opening 703 to provide a desired amountof preload in the spring to help achieve a desired clamping forcecharacteristic.

In use, jaw member 110 is initially in the open position. Tissue ispositioned between the jaw members 110 and 120. Proximal movement of themovable handle 40 causes distal movement of the drive element 150,which, in turn, causes jaw member 110 to rotate and move about the pivot222 and toward the jaw member 120 such that tissue may be clampedtherebetween. When the jaw members 110 and 120 are in the clampingposition, the compression spring 704 is configured to generate theappropriate closure force, e.g., in the range of about 3 kg/cm² to about16 kg/cm², between the jaw members 110 and 120.

With reference to the FIG. 8, jaw housing 817 includes a cut-out 803.Cut-out 803 is configured to house one or more types of resilientmembers 804. In the embodiment illustrated in FIG. 8, the resilientmember 804 is a monolithically formed resilient member in the form of acantilever spring 804 of suitable dimensions. The cantilever spring 804includes a generally elongated configuration and is disposed in anangled or oblique relation with respect to the longitudinal axis “A-A.”The angle at which the cantilever spring 804 is oriented ranges fromabout 0 to about 180°. In the embodiment illustrated in FIG. 8,cantilever spring 804 is oriented at an angle that ranges from about 45°to about 90°. Cantilever spring 804 includes a top portion 806 thatoperably couples to the drive element 150 by one or more suitablecoupling methods, e.g., rivet or pin 151. The cantilever spring 804 isdisposed above a pivot pin 822 to facilitate rotating the jaw member110. In the embodiment illustrated in FIG. 8, the cantilever spring 804does not maintain the jaw member 110 in either the open position or theclosed position.

In use, jaw member 110 is initially in the open position. Tissue ispositioned between the jaw members 110 and 120. Proximal movement of themovable handle 40 causes proximal movement of the drive element 150,which, loads spring 804, which, in turn, causes jaw member 110 to rotateand move about the pivot pin 822 and toward the jaw member 120 such thattissue may be clamped therebetween. When the jaw members 110 and 120 arein the clamping position, the cantilever spring 804 is configured togenerate the appropriate closure force, e.g., in the range of about 3kg/cm² to about 16 kg/cm², between the jaw members 110 and 120.

With reference now to FIG. 9, an alternate embodiment of a jaw housingis shown designated jaw housing 917. Jaw housing 917 is similar to thepreviously described jaw housings, e.g., jaw housing 117, and so as notto obscure the present disclosure with redundant information, only thoseoperative features and components that are unique to jaw housing 917 aredescribed.

Jaw housing 917 includes a proximal end 917 b that operably couples to adistal end of a resilient member (e.g., in the form of a tension spring904) by one or more of the previously described coupling methods, e.g.,rivets or, pin 151. A proximal end of the tension spring 904 operablycouples to the drive element 150 by one or more of the previouslydescribed coupling methods, e.g., brazing. Unlike the previouslydescribed jaw housings, e.g., jaw housing 117, a bottom portion 917 c ofthe jaw housing 917 operably couples to a pivot pin 922 that is fixedlycoupled to an internal frame of the shaft 12. Coupling the jaw housing917 in this manner facilitates rotating the jaw member 110 when thedrive element 150 is pulled proximally.

In use, jaw member 110 is initially in the open position. Tissue ispositioned between the jaw members 110 and 120. Proximal movement of themovable handle 40 causes proximal movement of the drive element 150,which, in turn, causes jaw member 110 to rotate and move about the pivotpin 922 and toward the jaw member 120 against the bias of the tensionspring 904 such that tissue may be clamped therebetween. When the jawmembers 110 and 120 are in the clamping position, the tension spring 904is configured to generate the appropriate closure force, e.g., in therange of about 3 kg/cm² to about 161 g/cm², between the jaw members 110and 120.

With reference now to FIGS. 10 and 11, an end effector 100 that utilizesa bilateral jaw configuration is shown. That is, both of the jaws 110and 120 move with respect to each other.

FIG. 10 illustrates an end effector 100 that includes jaw housings 1017and 1027 that are respectively associated with jaw members 110 and 120.It should be noted that, in one embodiment, jaw housings 1017 and 1027are substantially identical to each other, and, in view thereof, and soas not to obscure the present disclosure with redundant information, theoperative components associated with the jaw housing 1017 are describedin further detail with respect to jaw member 110, and only thosefeatures distinct to housing 1027 will be described hereinafter.

A proximal end 1017 b of the jaw housing 1017 operably couples to adrive element 250. A bottom portion 1017 c of the jaw housing 1017pivotably couples, via a pivot pin, e.g., a pivot pin 222, to acorresponding top portion 1027 d of the jaw housing 1027. A top portion1017 d of the jaw housing 1027 is operably coupled to a drive wire 250(or portion associated therewith) by one or more suitable couplingmethods previously described, e.g., brazing. Likewise, a bottom portion1027 c of the jaw housing 1027 is operably coupled to a drive element250 (or portion associated therewith) by one or more suitable couplingmethods previously described, e.g., brazing.

Unlike drive element 150, drive element 250 includes a bifurcated distalend 252 that includes two end portions 252 a and 252 b that arepivotably coupled to the drive element 250 and respective jaw housings1017 and 1027. End portions 252 a and 252 b are oriented in an angled oroblique relation with respect to each other and the longitudinal axis“A-A.” End portions 252 a and 252 b are configured to pivot from aninitially spaced-apart position that corresponds to the jaw members 110and 120 being in the clamping position (FIG. 10), to a subsequent orfinal position that corresponds to the jaw members 110 and 120 being inthe open position (not shown).

One or more resilient members are operably associated with the jawmembers 110 and 120. More particularly, a resilient member in the formof a compression spring 1004 is operably coupled to the end portions 252a and 252 b via one or more suitable coupling methods. The compressionspring 1004 is configured to expand and contract when the end portions252 a and 252 b move from the initial to the subsequent or finalposition.

In use, jaw members 110 and 120 are initially in the clamping positionunder the bias of the compression spring 1004. When the jaw members 110and 120 are in the clamping position, the compression spring 1004 isconfigured to generate the appropriate closure force, e.g., in the rangeof about 3 kg/cm² to about 16 kg/cm², between the jaw members 110 and120. Proximal movement of the movable handle 40 causes proximal movementof the drive element 250, which, in turn, causes the end portions 252 aand 252 b to move from the initial position towards the final position,which, in turn, causes the jaw members 110 and 120 to rotate and moveabout the pivot pin 222 and move away from one another. Thereafter,tissue is positioned between the jaw members 110 and 120. Subsequently,movable handle is released and the jaw members 110 and 120 move back tothe clamping position.

FIG. 11 illustrates an end effector 100 that includes jaw housings 1117and 1127 that are respectively associated with jaw members 110 and 120.It should be noted that, in one embodiment, jaw housings 1117 and 1127are substantially identical to each other, and, in view thereof, and soas not to obscure the present disclosure with redundant information, theoperative components associated with the jaw housing 1117 are describedin further detail with respect to jaw member 110, and only thosefeatures distinct to housing 1127 will be described hereinafter.

Similarly to that of bottom portion 1017 c of jaw housing 1017, a bottomportion 1117 c of jaw housing 1117 is pivotably coupled to acorresponding top portion 1127 d of jaw housing 1127. However, unlikejaw housing 1017, jaw housing 1117 includes a top portion 1117 d that isoperably coupled to a link assembly 1250, described in greater detailbelow.

A proximal end 1117 b of jaw housing 1117 is substantially resilient.More particularly, a notched out area 1103 of suitable dimensions allowsthe proximal end 1117 b to “flex” or give when a drive element 150 ismoved distally and the jaw members 110 and 120 move toward the clampingposition. In the embodiment illustrated in FIG. 11, the notched out area1103 includes a generally widened proximal end 1103 a and a tapered ornarrowed distal end 1103 b. This configuration of a widened proximal end1103 a and a tapered or narrowed distal end 1103 b facilitates flexingthe proximal end 117 b of the jaw housing 1117.

Jaw housing 1127 includes a similar notched out area 1203 of suitabledimensions that functions similarly to that of the notched out area 1103associated with jaw housing 1117.

Drive element 150 operably couples to the jaw housings 1117 and 1127 viathe link assembly 1250. In the illustrated embodiment, drive element 150operably couples to the link assembly via one or more suitable couplingmethods, e.g., a rivet or pin 1256. Drive element 150 is configured suchthat proximal movement of the movable handle 40 causes the drive element150 to translate distally, which, in turn, causes the jaw members 110and 120 to move from an open or neutral position to a clamping position.

Link assembly 1250 includes upper and lower links 1252 and 1254. Links1252 and 1254 include a generally elongated configuration. Links 1252and 1254 pivotably couple to each other via pivot pin 1256. Likewise,links 1252 and 1254 are pivotably coupled to a respective upper portion1117 d and lower portion 1127 c via respective pivot pins 1258 and 1260.Links 1252 and 1254 are configured to pivot about pivot pins 1256, 1258and 1260 when the drive element 150 is move distally. The links 1252 and1254 are configured to pivot from an initial or proximal position,wherein the links are slanted or oblique with respect to thelongitudinal axis “A-A,” through a transition or center point, whereinthe links 1252 and 1254 are in a substantially upright or perpendicularposition with respect to the longitudinal axis “A-A,” to a final ordistal position where the links 1252 and 1254 are again slanted oroblique with respect to the longitudinal axis “A-A” (FIG. 11).

A stop 1262 functions to provide the proper amount of movement of thelinks 1252, 1254 and drive element 150 when the drive element 150 ismoved distally such that a closure force in the range of about 3 kg/cm²to about 16 kg/cm² is present between the jaw members 110 and 120 whenthe jaw members 110 and 120 are in the clamping position. In theillustrated embodiment, stop 1262 includes a generally rectangularconfiguration. Stop 1262 may be made from any suitable materialincluding but not limited to metal, plastic, etc. In the illustratedembodiment, stop 1262 is monolithically formed with the end effector 100and includes a substantially rigid configuration. In certainembodiments, it may prove useful to make stop 1262 relatively resilient.Stop 1262 is configured to contact one of the links 1252 and 1254 and/ordrive element 150 when the drive element 150 is translated apredetermined distance distally within the shaft 12. More particularly,when the movable handle 40 moves proximally, the drive element 150 movesdistally, which, in turn, causes links 1252 and 1254 pivot aboutrespective pivot pins 1258 and 1260 and pivot pin 1256, from an initialposition that corresponds to the jaw members 110 and 120 being in theopen position, to a subsequent, or final, position that corresponds tothe jaw members 110 and 120 being in the clamping position (FIG. 11).When the drive element 150 including links 1252 and 1254 moves apredetermined distance, the stop 1262 and one of the links 1252, 1254and/or drive element 150 are configured to contact each other (FIG. 11).Contact between the stop 1262 and one of the links 1252, 1254 and/ordrive element 150 results in the proper amount of deflection for theproximal ends 1117 b and 1127 b and, thus, the necessary closure forceneeded between the jaw members 110 and 120. Stop 1262 prevents and/orimpedes further movement of the drive element 150 and the links 1252 and1254, which, in turn, maintains the jaw members 110 and 120 in theclamping position.

In use, jaw members 110 and 120 are initially in the open or neutralposition. Tissue is positioned between the jaw members 110 and 120.Proximal movement of the movable handle 40 causes distal movement of thedrive element 150, which, in turn, causes the links 1252 and 1254 tomove from the initial position through the center position and towardsthe final position, which, in turn, causes the jaw members 110 and 120to rotate and move about the pivot pin 222 and move toward each other.With the links 1252 and 1254 in this position, i.e., past the centerline of pins 1258 and 1260, the jaw member 110 and 120 will remain inthe clamped position in the absence of force on drive element 250,until, subsequently, movable handle 40 is moved distally to release thejaw members 110 and 120 and move them back to the open or neutralposition.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same. For example, other spring mechanisms such as, for example,compressed gas, resilient bladder, spring washers, bellows andcompressed air and so forth, may be operably associated with any of theaforementioned configurations of jaw housings, e.g., jaw housing 117,and utilized to generate a closure or sealing force at the jaw members.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

What is claimed is:
 1. An endoscopic forceps, comprising: a housinghaving at least one shaft that extends therefrom that defines alongitudinal axis therethrough; a drive assembly operably associatedwith the housing and including a drive rod; an end effector assemblyoperatively connected to a distal end of the at least one shaft andincluding a pair of first and second jaw members, at least one of thefirst and second jaw members being movable relative to other jaw memberfrom an open position wherein the first and second jaw members aredisposed in spaced relation relative to one another, to a clampingposition wherein the first and second jaw members cooperate to grasptissue therebetween; and a resilient member including a flexible uprightportion extending from, and integrally formed with, a proximal end ofthe at least one movable jaw member, the upright portion extendingupright relative to the longitudinal axis of the at least one shaft andsupporting an elongated member having a cam slot with a cam pin housedtherein, the resilient member operably coupled to the drive rod of thedrive assembly, wherein deflection of the resilient member provides aforce that biases the first and second jaw members in the clampingposition.
 2. An endoscopic forceps according to claim 1, wherein theresilient member and drive rod are configured such that proximalmovement of the drive rod causes the movable jaw member to move from theopen position to the clamping position.
 3. An endoscopic forcepsaccording to claim 1, wherein the upright portion of the resilientmember extends from a bottom wall of the proximal end of the at leastone movable jaw member.
 4. An endoscopic forceps according to claim 3,wherein the upright portion of the resilient member extends in agenerally orthogonal orientation from the bottom wall of the proximalend of the at least one movable jaw member.
 5. An endoscopic forcepsaccording to claim 1, wherein the cam pin is configured to translatewithin the cam slot when the drive rod is translated proximally.
 6. Anendoscopic forceps according to claim 1, wherein, when the cam pin istranslated proximally within the cam slot, a stop that is operablydisposed adjacent the cam slot contacts a trailing edge of the cam slot.7. An endoscopic forceps according to claim 1, wherein a leading end ofa stop is disposed in a generally orthogonal orientation with respect tothe cam slot.